Borders on having succeeded after one month (6)
I believe the answer is:
Here is my best explanation:
'borders' is the definition.
The answer and definition can be both man-made objects as well as being plural nouns.
Perhaps there's an association between them I don't understand?
'on having succeeded after one month' is the subsidiary indication.
'having' means one lot of letters go next to another.
'succeeded' becomes 's' (genealogical abbreviation).
'after' is a charade indicator (letters next to each other).
'one month' becomes 'apr' (Apr is an example).
'on' put next to 's' is 'ons'.
'ons' after 'apr' is 'aprons'.
(Other definitions for aprons that I've seen before include "Paved areas for out-of-use aircraft", "Kitchen garments for cooks", "Garments worn in kitchens", "Kithchen garments or airfield areas", "Protective garments for aircraft", "Areas for parking aircraft", "Paved areas for parking aircraft", "Protective garment" and "Areas for parked aircraft".)